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Locations of records in A177942.
2

%I #8 Dec 14 2018 06:06:34

%S 1,3,4,9,11,13,20,33,42,49,84,86,107,109,123,128,191,295,296,318,330,

%T 337,396,453,481,616,663,771,882,1105,1180,1257,1431,1659,1856,1936,

%U 2130,2370,2584,2651,2790,2959,3009,3080,3121,3189,3503,3639,3879,3902,3961

%N Locations of records in A177942.

%C Also: indices m for which A177941(m)-2 and A177941(m)+2 are cousin primes (A023200).

%o (PARI) listai(nn) = {my(va = vector(nn), rec = 0, ind = 1); va[1] = 5; for (n=2, nn, p = factor(va[n-1]^2-4)[1,1]; if (p > rec, print1(n-1, ", "); rec = p); va[n] = va[n-1] + p - 1;);} \\ _Michel Marcus_, Dec 14 2018

%Y Cf. A177941, A177942, A023200, A177929, A177930, A177931, A177945

%K nonn

%O 1,2

%A _Vladimir Shevelev_, May 15 2010

%E 1 inserted, a(10) corrected and sequence extended by _R. J. Mathar_, Jun 30 2010

%E More terms from _Michel Marcus_, Dec 14 2018